The bill requires a woman seeking an abortion to first undergo an ultrasound to determine gestation age of the unborn child.

Opponents of the measure said that the procedure is "costly and medically unnecessary..."

"This version of the ultrasound bill has unmasked its true purpose," said House Democratic Leader David Toscano (D-Charlottesville). Toscano said that the bill has nothing to do with health or safety.

"It is about forcing women to undergo – and physicians to administer – a costly and medically unnecessary procedure that provides little useful information and serves simply to intimidate women, their families, and their doctors," said Toscano, in a release.

Lawmakers amended the bill more than once prior to passage. Yet opponents of the bill saw no improvement. "This amended version is even worse than the original bill," said Del. Vivian Watts (D-Fairfax).

The original version of the bill required women seeking an abortion first undergo a transvaginal ultrasound to determine gestation age.

However, after pressure from Virginia Governor Bob McDonnell, the bill was amended to require women have a less invasive external abdominal ultrasound.

The bill was further amended to exclude abortions performed in cases of rape or incest.

The Virginia Senate passed the bill Tuesday afternoon by a vote of 21-19. [Read the bill]

Governor McDonnell said he would sign the bill into law once it passed both the Senate and the House of Delegates. The governor's spokesperson said that McDonnell has seven days to act upon it upon receiving it.

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